2.) I need to understand the steps on how to do this problem. the answer is already in picture just trying to understand how to get to that. thank you!!!

Assume that 1 unit of Currency Y costs 0.49 units of Currency X,1 unit of Currency Z costs 7.99 units of Currency Y, and 1 unit of Currency Z costs 4.00 units of Currency X. By what percent is Currency Z mispriced relative to Currency Y ? If Z is overpriced, type a positive number and if Currency Z in underpriced, type a negative number. Go out four decimals - for example, if Z is underpriced by 2.25%, type -.0225 . Answer: First, take the other two exchange rates ( X vs, Y and X vs, Z ) and then use basic algebra to figure out what the Y vs. Z rate should be. We call this the cross rate. Then compare what it should be to what it actually is the way we did it in class and in your practice problems. Take that difference as a percentage of what it should be and you know just how much Currency Z is mispriced. The correct answer is: -0.0212